Posterior Fossa ve Pineal Bölge Cerrahisinde Yarı Oturur Pozisyon: Tek Merkezli Deneyim

Öz

Amaç: İntrakraniyal cerrahide yarı oturur pozisyon; beyin omurilik sıvısı ve venöz kanın yerçekimiyle daha iyi drenajı, daha net görüş alanı, azalmış intrakraniyal basınç ve minimal serebellar retraksiyon gibi önemli cerrahi avantajlar sağlar. Tarihsel olarak venöz hava embolisi gibi komplikasyonlarla ilişkilendirilmiş olsa da, anestezi yönetimi ve intraoperatif izlemdeki son gelişmeler bu pozisyonun güvenliğini belirgin şekilde artırmıştır. Gereç ve Yöntemler: 2019 ile 2024 yılları arasında, deneyimli bir beyin cerrahı tarafından tek bir merkezde yarı oturur pozisyonda gerçekleştirilen ardışık 17 intrakraniyal cerrahi olgusu retrospektif olarak analiz edildi. Hastaların demografik verileri, lezyon özellikleri, cerrahi ayrıntılar ve klinik sonuçları incelendi. Preoperatif kardiyak değerlendirme ile belirgin sağdan sola intrakardiyak şant dışlandı. İntraoperatif olarak venöz hava embolisini saptamak amacıyla sürekli end-tidal CO₂ monitörizasyonu kullanıldı. Bulgular: Lezyonlar serebellum ve pineal bölgede yer alan çeşitli intrakraniyal patolojileri kapsamaktaydı. On beş olguda (%88) total rezeksiyon sağlandı. Hiçbir olguda klinik olarak anlamlı venöz hava embolisi ya da diğer intraoperatif komplikasyon gözlenmedi ve hiçbir hastada postoperatif nörolojik defisit gelişmedi. Bulgularımız, uygun cerrahi teknik ve perioperatif protokollerle uygulandığında yarı oturur pozisyonun güvenli ve etkili olduğunu gösteren güncel literatürü desteklemektedir. Retrospektif tasarım, küçük örneklem hacmi ve yüksek duyarlılıklı izlem araçlarının kullanılmamış olması gibi sınırlılıklar bulunsa da, elde edilen veriler ciddi komplikasyon oranlarının düşük olduğunu bildiren son çalışmalarla uyumludur. Sonuç: Yarı oturur pozisyon, seçilmiş intrakraniyal cerrahilerde güvenli ve avantajlı bir cerrahi yaklaşım olarak öne çıkmakta; üstün cerrahi görüş alanı ve düşük komplikasyon oranları ile olumlu klinik sonuçlar sunmaktadır. Bu bulguların güçlendirilmesi için daha büyük hasta serilerini içeren, karşılaştırmalı ve ileriye dönük çalışmalar önerilmektedir

Anahtar Kelimeler

• Yarı oturur pozisyon
• Posterior fossa cerrahisi
• Kraniotomi
• Hava embolisi

Semi-Sitting Position in Posterior Fossa and Pineal Region Surgery: Single-Center Experience

Öz

Aim: The semi-sitting position for intracranial surgery provides substantial surgical advantages, including improved gravitational drainage of cerebrospinal fluid and venous blood, clearer visualization, reduced intracranial pressure, and minimized cerebellar retraction. Although historically associated with complications such as venous air embolism, recent advancements in anesthetic management and intraoperative monitoring have markedly enhanced its safety profile Material and Methods: We retrospectively analyzed 17 consecutive intracranial surgeries performed in the semi-sitting position at a single center between 2019 and 2024 by a senior neurosurgeon. Patient demographics, lesion characteristics, surgical details, and outcomes were reviewed. Preoperative cardiac evaluation excluded patients with significant right-to-left intracardiac shunts. Continuous end-tidal CO₂ monitoring was used intraoperatively to detect venous air embolism. Results: Pathologies included diverse intracranial lesions in the cerebellum and pineal region. Gross total resection was achieved in 15 cases (88%). No clinically significant VAE or other intraoperative complications were detected, and no postoperative neurological deficits occurred. Our series supports the growing body of evidence that semi-sitting position is both safe and effective when applied with appropriate technique and perioperative protocols. Despite limitations related to retrospective design, small sample size, and the absence of highly sensitive monitoring tools, our findings are consistent with recent literature reporting low rates of serious complications. Conclusion: The semi-sitting position remains a viable and advantageous surgical approach for selected intracranial procedures, offering excellent surgical exposure and favorable clinical outcomes with minimal complication rates. Further prospective studies with larger cohorts and comparative controls are recommended to reinforce these findings.

Anahtar Kelimeler

• Semi-sitting position
• Posterior fossa surgery
• Craniotomy
• Air embolism

Etik Beyan

The study was conducted in accordance with the rules of the Declaration of Helsinki and approved by the Ethics Committee of Pamukkale University (09.07.2025/E-60116787-020-719081)

Kaynakça

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